Tests for Alzheimer’s Disease
For an affirmative diagnosis of Alzheimer’s disease, a series of thorough assessments are required to eliminate the possibilities of all other diseases.
A certified healthcare professional will review any past or current illness and medication. He will also look into the medical condition of close relatives to see if there are any other influencing factors for Alzheimer’s disease.
Physical Exam and Diagnostic Tests
Blood and urine samples are collected for diagnostic testing and a physical exam is carried out by a certified healthcare professional to understand the following:
- Diet, medication and consumption of alcohol.
- Blood pressure, temperature and pulse.
- Heart and lung health.
- Overall health assessment.
A healthcare professional will carry out a neurological examination for the following:
- Coordination, muscle tone (continuous and passive partial contraction of the muscles) and strength
- Eye movement
- Touch sensation
Structural, functional and molecular imaging techniques are employed for Alzheimer’s diagnosis.
Structural imaging (magnetic resonance imaging (MRI) and computed tomography (CT)) provide details of the shape, position or volume of brain tissue. Shrinkage of particular brain regions such as hippocampus might be an early sign of Alzheimer’s disease.
- Test for tumors, sign of small or large strokes, damage from head trauma or an increase of fluid in the brain. These tests are principally used to eliminate other conditions that may cause symptoms similar to Alzheimer’s disease but require different treatments.
Brains scans serve as part of the diagnosis of Alzheimer’s disease.
Functional imaging reports the working efficiency of cells in various brain regions, they present the cell activity on sugar or oxygen. Reduced brain cell activity in certain brain regions, such as reduced use of sugar (glucose) in brain regions critical for memory, learning and problem solving has been reported in Alzheimer’s disease patients. Functional imaging techniques include positron emission tomography (PET) and functional MRI (fMRI).
Molecular imaging detects pathological changes linked to Alzheimer’s disease, such as amyloid plaques in the brain, with the use of molecular imaging tracers, and monitors disease progression. Molecular imaging techniques include PET, MRI and single photon emission computed tomography (SPECT).
A certified healthcare professional would also assess a person’s sense of well-being, by attempting to detect signs of depression or other mood disorders that may contribute to memory problems and other symptoms that may overlap with dementia.
Mental Status Test
1. Mini-mental state exam (MMSE)
- Cognitive screening tool developed by Folstein MF et al., 1975.
- A set of paper with 11 questions on a 30-point scale designed to help in the diagnosis of dementia and assessment of its progression and severity.
- Different mental abilities including memory, concentration and language are tested.
- On average, the MMSE score of an Alzheimer’s patient decreases about 2 to 4 points each year.
2. Mini-cog test
- A 3-minute test used to screen for cognitive impairment in older adults during the primary care setting (Borson S et al., 2000; Borson S et al., 2003; Borson S et al., 2006).
- Mini-cog test is at least twice as fast as MMSE and is less affected by the subject’s ethnicity, language, and education. It can be used to determine the variety of different dementia.
- This test can also be used to detect patients with mild cognitive decline.
- During the mini-cog, a person will be requested to complete two tasks:
Remember three common items and repeat in a few minutes.
Draw the face of a clock showing all 12 numbers in the right places and a time specified by the examiner.
3. The Saint Louis University Mental Status Examination (SLUMS)
- SLUMS consists of 11 questions on a 30-point scale and takes approximately 7 to 10 minutes to execute (Gugala M et al., 2007).
- This test is useful for diagnosis of mild cognitive impairment and dementia.
- The areas of assessment in this test encompass cognition, reasoning, attention, working memory, problem solving, language and mental health.
- Compared to MMSE, this test includes more areas and is useful in detecting mild-cognitive impairment in non-demented people (Szcześniak D & Rymaszewska J, 2015).
SLUMS test is free and can be downloaded online here
4. Montreal Cognitive Assessment (MoCA)
- MoCA was designed as a rapid cognitive screening tool for mild cognitive impairment (Nasreddine ZS et al., 2005).
- This test takes approximately 10 minutes to execute and the total score is 30 points, a score of 26 or above is considered as normal.
- This test assesses different mental abilities: visuospatial skills, executive functions, memory, attention, language, conceptual thinking, calculations and orientation.